Steam generator



June 16, 1936. w. R. WOOD 2,044,279

STEAM GENERATOR Filed June 19, 1934 3 Sheets-Sheet 1 INVENTOR f BY ATTORNEY-3 June 16, 1936. w. R. WOOD STEAM GENERATOR Filed June 19, 1934 5 Sheets-Sheet 2 INVENTOR 16, 1936. w. R. WOOD STEAM GENERATOR Filed June 19, 1934 3 Sheets-Sheet 5 ATTORNEIY Patented June 16, 1936 2,044,270 STE GENERATOR Wilfred Rothery Wood, New York, N. Y., assignor to Combustion Engineering Co. Inc., New York, N. Y., a corporation of Delaware Application June 19, 1934, Serial No. 731,223

18 Claims.

This invention relates to steam generators and has for its primary object the provision of an inexpensive high capacity steam generator occupying a minimum of floor space.

More specific objects relate to certain improved features of construction and combinations of parts hereinafter fully described.

How the foregoing togetherwith such other objects and advantages as may hereafter appear or are incident to my invention are realized'is illustrated in preferred form in theaccompanying drawings, wherein:-

Fig. 1 is a sectional elevation through a steam generator constructed in accordance with my invention, the section being taken substantially on the line I-I of Fig.

Fig. 2 is an enlarged plan section taken substantially on the line 2-2 of Fig. 1;

Fig. 3 is an enlarged plan section taken substantially on the line 3-3 of Fig. 1;

Fig. 4 is an enlarged plan section through the upper drum of Fig. 1 and taken on the line 3-4;

Fig. 5 is an enlarged fragmentary view of a tube detail;

Fig. 6 is a plan section taken on the line B6 of Fig. 5; and

Fig. '7 illustrates a modification construction of the lower portion of my steam generator.

My improved steam generator is of vertical cylindrical or circular form and comprises in general an upright lower water drum 8, an upright upper steam and water drum 9 spaced above and aligned with the lower drum 8, a plurality of upright boiler tubes connecting said drums, a combustion chamber In and burner means II for admitting fuel and air into the combustion chamber.-

The upright boiler tubes are arranged in two circular groups I2 and I3 with the inner group I2 comprising a plurality of concentric rows of circularly arranged tubes It, I5, I6, and I1, and the outer group a row of circularly arranged tubes I8, although the number of rows of tubes in the groups may be altered as desired. The outer group or ring of tubes I3 is radially spaced from the inner group or cylindrical bank I2 so that an annular space is provided therebetween which constitutes the combustion chamber II), it being pointed out that the chamber is relatively narrow, which together with the type of firing,'produces high flame velocities.

The upright boiler tubes are bent at their lower and upper ends for direct connection into the lower and upper drums 8 and 9 respectively,

it being noted that the tubes I8 of the outer group I3 connect into the steam space of the drum 9 as do also certain of the tubes of the group I2, for example the tubes of the row It, and that the remaining rows of tubes of the inner group connect into the water space of said drum. The boiler tubes enter the drums radially and are arranged in a plurality of groups circumferentially of the drums each consisting of a number of tubes successively entering the drums at higher points as indicated at I9 in the upper drum of Fig. 1.

Suitable sheathing or sectional casing structure 20 backs the outer ring of tubes I3 and the spaces between the tubes of the outer row M of the inner bank are closed as by means of metallic blocks 2i, preferably of wedge shape and cemented together (see Figs. 5 and 6). Such blocks or similar means may also be employed between the tubes I8 of the ring It. The surrounding sheathing 20 and the blocks 25 end short of the top of the boiler to permit of flow of the products of combustion in a manner hereinafter appearing.

It will be seen from the foregoing that closed inner and outer steam evaporating walls are provided for the annular combustion chamber It. The combustion chamber III is provided with a. bottom 22 supported by the tubes It at their lower portions and adapted to retain molten slag which may be removed intermittently or continuously as by means of a tap 23 to maintain a predetermined level of the slag. An annular member 24 extending downwardly from the outer ring of tubes It of the inner bank completes the bottom construction.

Fuel, preferably pulverized coal, is introduced into the lower portion of the combustion chamber by means of the peripherally arranged nozzles lLand in this instance I have shown four such nozzles equally spaced circumferentially of the combustion chamber and positioned to introduce the fuel in a manner to produce a swirling flame sweeping over the wall tubes and spiralling upwardly through the chamber. Air, preferably preheated, is admitted with the fuel by means of damper controlled air passages 25 in which the nozzles II are located, the air being supplied to the passages from a conduit 26 in the form of ring having an inlet 21 for the preheated air.

Similarly, a conduit 28 in the form of ring hav-" ing a fuel inlet 29, supplies the nozzles II with fuel. The conduits 26 and 28 are made in sections for assembling purposes and the air conduit 26 is provided with doors 30 opposite the nozzles and air passages through which access may be had to the nozzles and combustion chamher.

At the upper portion of the boiler a chamber 3| is provided in surrounding relation to the upper drum 9. This chamber is preferably of greater diameter than the boiler proper and has a superheater 32 located in the enlarged portion.

The superheater comprises upright superheater tubes 33, radially disposed as illustrated in Fig. 2, and directly connected at one end into the upper portion of the drum 9 as indicated at 34 in Fig. 1, to receive steam. At their other ends these tubes are connected into a circular header 35 from which the superheated steam is withdrawn for delivery to the point of use. The cylindrical casing of the chamber 3| is made up of a plurality of removable sections 3la whereby the superheater may be readily inspected and repaired, it being pointed out that the complete superheater will be exposed upon removal of the casing sections because of its peripheral location.

The upper chamber 3| is in communication with the combustion chamber l by means of the outlet 36 through which the products of combustion pass upwardly into the chamber 3!. Baflie means 37 of annular form is provided in the chamber 3| for directing the products of combustion upwardly over the superheater 32 and from thence downwardly over and among the tubes of the inner bank I2. The products of combustion exit through an oiftake 38 at the lower portion of the bank l2.

The amount of gases passing over the superheater is controlled by means of adjustable bypass dampers 39 associated with the baffle means 31 whereby a portion of the gases may be made the combustion chamber over the inner bank of tubes l2. The bank of tubes I2 may be baiiied as indicated at 40 to better distribute the gases over the tubes.

Referring now to the upper steam and water drum 9, it is to be observed that because of its height and vertical disposition as much as 50% of the steam is made and discharged above the water level. However, water will be lifted with the steam that is discharged into the drum but as the upward velocity in the drum is comparatively low, much of the water will fall out of the steam before it reaches the top of the drum where the super-heater tubes enter it. The large space between the water level and the point where the steam is taken ofi not only affords great opportunity for the Water to fall out of the steam but also provides room for a very effective form of water separator for insuring dryer steam.

In Figs. 1 and 4, I have illustrated a separator 4| of cylindrical form comprising a tapered casing 42 having a. bottom 43, a top 44, and a plurality of peripherally arranged vanes 45 immediately below the top 44 providing a plurality of tangential steam inlets to the interior of the casing 42. The diameter of the top equals that of the interior of the drum and this top is located just below the points of connection 34 of the superheater tubes so that the steam and the water carried thereby cannot enter the superheater before separation is effected in the separator. The diameter at the vanes 45 is suificiently less than the inner diameter of the drum to permit the steam to enter the separator and after it passes thru the vanes it passes downwardly and then upwardly thru the cylindrical outlet 46 located centrally of the top plate and extending down I in diameter.

into the casing 4|. Water is led-from the casing 42 to the water space of the drum by means of a downwardly extending pipe 41, the lower end of which is submerged in the water in the drum.

48 are provided in the drums.

In the modification illustrated in Fig. 7. the lower portion of the combustion chamber In is enlarged and the boiler tubes l8 are suitably bent to follow the contour of the enlargement. The tubes of both groups may be connected into the drum in a mannersimilar to that shown in Fig. 1. In this instance, I have shown the fuel and air admitted by means of downwardly directed inclined fuel and air nozzles 49 and 50 respectively.

As illustrated in Fig. 1, it will be seen that the boiler parts are supported from the lower drum which rests on a support whereby expansion is in an upward direction. The top wall 52 of the casing surrounds the upper drum 9 and a yieldable joint is provided at 53 between the top wall and the drum so that the drum may freely move up and down with respect to the casing as expansion and contraction takes place.

The general proportions of the installation may be arrived at from the drums which are 42 inches The heating surface is approximately 3200 sq. ft. with a steaming capacity of about 45000 lbs. from and at 212 degrees. The

combustion space is approximately 1050 cu. ft. with a rate of combustion of about 42000 B. t. u. per hour. The annular velocity near the bottom of the combustion space is about 4200 ft. per

minute, with an upward flow of about 2000 ft.

per minute. The gas near the bottom rotates at a speed corresponding to about 160 per minute. The temperature leaving the furnace is from about 1200 to 1400 degrees F.

No specific claim is made herein to the steam and water separator illustrated in Figures 1 and 4, as claims directed thereto have been made part of the subject-matter of a divisional application, Serial No. 42,423, filed September 27th, 1935.

I claim:

1. A steam generator comprising upright upper and lower drums, upright boiler tubes connected at their lower ends directly into the lower drum and at their upper ends directly into the upper drum,

chamber being unobstructed in the portion between the point of fuel admission and said bottom.

2. A steam generator comprising upright upper upright boiler tubes connectmg said drums arranged in an inner and an outer circular group with an annular space therebetween, said circular space constituting a combusmeans associated with tubes of said irmer group whereby the inner tubes of the group are subject to heat of convection and the outer tubes to radiant heat, said inner tubes constituting downcomer tubes and said outer tubes 3 constituting upcomer tubes, and said outer circular group of tubes comprising upcomer tubes, means for introducing fuel into said chamber, means providing a passage for leading gases from said chamber to said inner group of tubes at one end portion thereof, and a gas oiftake at the other end portion of said inner group of tubes.

3. A steam generator comprising an upright annular combustion chamber having its upright walls defined by steam evaporating tubes subject to radiant heat, a slag retaining bottom for said chamber, means for introducing fuel into the lower portion of said chamber to be burned in space therein, and an outlet for the products of combustion at the upper portion of said chamber, said annular combustion chamber being unobstructed in the portion between the point of fuel admission and said bottom.-

4. A steam generator comprising an upright annular combustion chamber having upright walls comprising steam evaporating tubes subject to radiant heat, a slag retaining bottom for said chamber, means for introducing fuel into the lower portion of said chamber to be burned in space therein, upright convection tubes of the generator surrounded by said combustion chamber, means providing a gas passage leading from the upper portion of said chamber to theupper portion of said convection tubes, and an offtake for the products of combustion at the lower portion of said convection tubes.

5. A steam generator comprising vertically spaced and aligned upright drums, boiler tubes connected at the lower ends into the lower of said drums and at their upper ends into the upper of said drums, a plurality of said tubes being arranged circularly in an inner group and the remainder in a ring radially spaced from said inner group to provide an annular space therebetween constituting a combustion chamber, a slag retaining bottom for said chamber, means for introducing fuel into said chamber at the lower portion thereof, baffle means at the upper portion of said chamber whereby the products of combustion leaving the chamber are directed upwardly then downwardly and over and among the tubes of the inner group, and an ofitake for the products of combustion at the lower portion of said inner group and a superheater located between said chamber and said inner group of tubes.

6. A steam generator comprising upright upper and lower drums, upright boiler tubes connecting said drums circularly arranged in outer and inner groups with an annular space therebetween constituting a combustion chamber, said outer group comprising radiant heat tubes and said inner group comprising means dividing the tubes thereof into outer tubes subject to radiant heat and inner tubes subject to heat of convection, means for introducing fuel to be burned in space in said combustion chamber, means providing a gas passage leading from said combustion chamber to said inner group of tubes at one end portion thereof and an offtake for the products of combustion at the other end portion of said inner group of tubes.

7. A steam generator comprising a lower water chamber, an upper steam and water chamber, upright boiler tubes connecting said chambers circularly arranged in inner and outer groups with an annular'space therebetween, means for introducing fuel to be burned in space in said annular space, the tubes of the outer group being subject to radiant heat and being connected into the steam space of the upper chamber, and means dividing the tubes of the inner group into outer tubes subject to radiant heat and inner tubes subject to heat by convection, certain tubes of said inner group being connected into the steam space of the upper chamber and the remaining ones into the water space of said upper chamber.

8. A steam generator comprising a. lower upright drum, an upper upright drum, a bank of upright boiler tubes connecting said drums, said bank having an outer row of circularly arranged 5 relatively closely spaced tubes with means filling the spaces for the major portion of the height of said tubes, a. plurality of upright boiler tubes connecting said drums arranged in the form of a ring in surrounding spaced relation to said bank of tubes, the annular space between said bank and said ring of tubes constituting a combustion chamber, a bottom for said annular combustion chamber, means for introducing fuel and air into the lower portion of said chamber, an outlet at the top of said chamber for the products of combustion, a chamber in surrounding relation to said upper drum, 8, superheater in said upper chamber, baflie means associated with the combustion chamber outlet for directing the products of combustion over said superheater and over and among the aforesaid bank of tubes, and an oiftake for the products of combustion at the lower portion of said bank.

9. A steam generator comprising upright upper and lower drums, upright boiler tubes connecting said drums circularly arranged in outer and inner groups with an annular space therebetween, means filling the spaces between the outer tubes of said inner group for the major portion of their height, means for introducing fuel into the lower portion of said space for burning in an upwardly moving flame, an outlet for the products of combustion at the upper portion of said space,

a chamber above and in communication with said annular space, a superheater in said chamber, means for directing fiow of the products of combustion over said superheater and over and among the inner tubes of said inner group of boiler tubes, and an oiftake for the products of combustion at the lower portion of the inner tubes of said inner group of boiler tubes.

10. A steam generator comprising upright upper and lower drums, upright boiler tubes connecting said drums circularly arranged in groups with an annular space therebetween, means for introducing fuel into the lower portion of said space for burning in an upwardly moving flame, an outlet for the products of combustion at the upper portion of said space, a circular chamber in surrounding relation to said upright upper drum and in communication with said annular space, and a superheater in said space having its tubes connected directly into said upper drum to receive steam therefrom.

11. A steam generator comprising uright upper and lower drums, upright boiler tubes connecting said drums circularly arranged in outer and inner groups with an annular space therebetween, means filling the spaces between the outer tubes of said inner group for the major portion of their height, means for introducing fuel into the lower portion of said space for burning in an upwardly moving flame, an outlet for the products of combustion at the upper portion of said space, a chamber above and in communication with said annular space, a superheater in said chamber, baflie means for directing fiow of the products of combustion over said superheater and over and among the inner tubes of said inner group of boiler tubes, said baffle means being adjustable to control flow over the superheater, and an ofitake for the products of combustion beyond said inner group of tubes.

12. A steam generator comprising upright upburning in an upwardly moving flame, an outlet for the products of combustion at the upper portion of said space, a chamber above and in communication with said annular space. a superheater in said chamber, banie means for directing flow of the products of combustion over said superheater and over and among the inner tubes of said inner group of boiler tubes, and a bypass damper associated with said baiile means for controlling the flow over the superheater.

13. A steam generator comprising an upright annular combustion chamber having upright walls comprising upright steam evaporating tubes subject to radiant heat and heat of convection, means for introducing fuel into the lower portion of said chamber to be burned in an upwardly moving spiral flame, upright downcomer tubes for the generator surrounded by said chamber, means providing a gas passage for leading gases from said chamber to the upper portion of said downcomer tubes, and an offtake for the gases at the lower portion of said downcomer tubes whereby the gases flow downwardly over and among said tubes.

14. A steam generator comprising an upright annular combustion chamber having its upright walls comprising upright steam evaporating tubes subject to radiant heat and heat of convection, means for introducing fuel into the lower portion of said chamber to be burned in an upwardly moving spiral flame, upright downcomer tubes for the generator surrounded by said chamber, means providing a gas passage for leading gases from said chamber to the upper portion of said downcomer tubes, an ofl'take for the gases at the lower portion of said downcomer tubes, whereby the gases flow downwardly over and among said tubes, and battles associated with said tubes.

15. A steam generator comprising upright upper and lower drums, upright boiler tubes connecting said drums circularly arranged in groups with an annular space therebetween, means for introducing fuel into the lower portion of said space for burning in an upwardly moving flame, an outlet for the products of combustion at the upper portion of said space, means per and lower \ciirrums, upright boiler tubes 10 connecting said ums circularly arranged in groups with an annular space, therebetween, means for introducing fuel into the lower portion of said space for burning in an upwardly moving' flame, an outlet for the products of combustion at the upper portion of said space,circular casing structure providing 'a chamber above and in communication with said annular space, a peripherally located superheater in said chamber, said casing structure comprising removable sections adapted, when removed, to afford compiete exposure of said superheater, and an oil'- take for the products oi. combustion beyond said superheater.

17. A steam generator comprising upright upper and lower drums, upright boiler tubes connecting said drums circularly arranged in groups with an annular space therebetween, means for introducing fuel into the lower portion of said space for burning in an upwardly moving flame,

an outlet for the products of combustion at'the upper portion of said space, casing structure comprising a plurality of removable sections circulally arranged to provide a chamber in surrounding relation to said upright upper drum and in communication with said annular space, and an upright superheater in said chamber circularly arranged adjacent said removable sections whereby complete exposure of the superheater may be aiforded upon removal of said 40 sections.

18. A steam generator comprising an upright annular combustion chamber having a ring of upright radiant heat tubes at its outer wall, a ring of upright radiant heat wall, means closing the spaces between the tubes at said inner wall, said chamber having an outlet at its upper portion communicating with the space within said second ring of tubes, upright tubes located in said space subject to the heat of 50 the gases entering said space through said outlet, and an oiftake at the bottom portion of said space.

WIILFRED ROTHERY WOOD.

tubes at its inner 

